I know there is a special clause in Haaland's contract. At the end of this year, it will be possible to transfer with an active substance and a certain testimonial fee. Borussia Dortmund is very strong economically. They usually bring young and potential football players to the world market. They usually make very good profits, although sometimes they can't do what they want. They will also make a good income in the Haaland transfer. They could also find another young player with potential to replace Haaland. Dortmund's Scout team is one of the best in the world.
something Dortmund does every season. after they bought young players and made them world-class players. they will sell it at a high price. Haaland is a good player, and his transfer value is also reportedly high. it would be an advantage for Dortmund. and they know very well how to make a profit with what they do.
It is not about selling players for a lot of money, it is about where they are spending that money which ends up not being great. I mean they keep getting better and better younger players and spending more and more for them, but they end up selling people for tens of millions of euros every single season and end up not getting any star level players, or even be competing with Bayern to win the title. Yes they are second ranked right now but nobody really believes they will be champions, do they? So you can get 100 young players, raise them for 5 seasons, and sell all 100 and make a billion dollars if you want, if you do not use that money to build a roster with amazing potential, then you are spending that money on something useless. I am guessing that they are improving their youth setup constantly every year and growing in nations they exist as well to get more players from those nations, but its still not good enough for today, maaaybe it will help in the future.